Fabrication of n‐p heterostructure of polyaniline–barium zirconate nanocomposites sensor device for the detection of diazomethane gas

Nanoparticles of barium zirconate were prepared by sol–gel method and used for the preparation of nanocomposites. Polyaniline fibers and its nanocomposites with barium zirconate were prepared by in‐situ polymerization at various percentages of 1 wt%, 2 wt%, 3 wt%, 4 wt%, and 5 wt%. The prepared polyaniline nanocomposites were subjected for determination functional group by FTIR spectra and XRD analysis. The surface morphology is important aspect of sensor studies, which is illustrated by SEM and TEM image. DC conductivity of the pristine PANI and its nanocomposites increases with increase in temperature up 200°C. It is evident that the increase in conductivity is due to the hopping of charge carriers from valence band to conduction band. Among all the nanocomposites, 3 wt% of polyaniline nanocomposite shows the high conductivity of 18.6 S/cm. It is also noted that 3 wt% polyaniline nanocomposites have a higher sensitivity of 86.2% at 300 ppm when compared with other compositions. This could be because of formation strong connections between the polyaniline fibers and nano‐oxide as a resulted of enhanced node connections, high surface area and porosity through optimized nanomaterials doping. The nanocomposites sensitivity restored in 89 s after the gas was removed, responding in 23 s at 300 ppm.